Devices for print imaging have been diversified, and presently print imaging devices widely used mainly include: inkjet printers, laser printers, LED printers, stylus printers and thermal printers. During a printing process, a print imaging device consumes coloring materials, such as ink and toner, and the coloring materials are generally placed in a consumable cartridge so as to be supplemented and replaced conveniently.
In order to record information such as a source and usage of the consumable cartridge, a consumable chip which can electrically record the information is provided on the consumable cartridge. In this way, in a case that the coloring materials in the consumable cartridge are consumed up, a user can supplement the coloring materials by replacing the box consumables. The print imaging device electrically reads information stored on the consumable chip, thereby updating a state of the print imaging device timely and automatically without manually inputting information by the user, such as a type and a production date of the consumable cartridge.
Some conventional print imaging devices read information stored on the consumable chip or write information into the consumable chip by way of a connection shown in FIG. 1. As shown in FIG. 1, a current source 101 and a voltage source 102 are provided in the print imaging device. An output voltage of the voltage source 102 is 16V, and a drive current of the voltage source 102 is greater than 10 mA. A drive current of the current source 101 is 1 mA, and an amplitude of a highest voltage of the current source 101 is 15V. Under the control of a controller 103, a toggle switch 104 may switch between outputting a current source signal and outputting a voltage source signal to a signal line ID.
The signal line ID is connected to a consumable chip 105. When performing a reading operation, the print imaging device outputs a current source signal to the signal line ID and detects a voltage of the signal line ID with an ADC 106, thereby reading data stored in the consumable chip. When performing a writing operation, the print imaging device outputs a voltage source signal to the signal line ID, thereby writing data to be written into the consumable chip.
In practice, the issue that how to accurately determine, by the consumable chip, whether the print imaging device needs to perform a reading operation or a writing operation based on the signal transmitted through the signal line ID is not addressed well, thereby resulting in error responses of the consumable chip.